Handshake correction apparatus of photographing apparatus

ABSTRACT

Disclosed is a handshake correction apparatus of a photographing apparatus. The handshake correction apparatus includes a lens support plate that supports a correction lens and operates in a direction perpendicular to an optical axis; a base that supports the lens support plate to be movable; and magnets and driving coils which are assembled on the lens support plate and the base to face each other, wherein the magnets are tight-fitted in assembly grooves of the lens support plate or the base, and wherein one or more protrusions that protrude from internal walls of the assembly grooves toward the magnets and elastically press the magnets are formed in the assembly grooves. Control performance of a correction operation of the handshake correction apparatus may be improved by ensuring alignment between assembly structures of assembly parts including magnets and yokes.

CROSS-REFERENCE TO RELATED PATENT APPLICATION

This Application is a continuation of U.S. patent application Ser. No.12/710,495, filed Feb. 23, 2010, which claims the priority benefit ofKorean Patent Application No. 10-2009-0022759, filed on Mar. 17, 2009,in the Korean Intellectual Property Office, the entirety of which isincorporated herein by reference.

BACKGROUND

The present invention relates to a handshake correction apparatus of aphotographing apparatus, and more particularly, to a handshakecorrection apparatus capable of correcting image blur caused by the handof a user shaking.

Digital cameras capture an image of a subject, convert the image intoimage data, and record the image data in an appropriate file format. Ifthe captured image is affected by the hand of a user shaking or externalvibration, the captured image may be blurred, thereby having lowquality.

Currently, various image stabilization techniques for automaticallycorrecting camera shake have been developed. For example, a method offixing an image-forming location on an image sensor by driving andcontrolling an optical lens to move by an appropriate amountcorresponding to camera shake has been considered. In this case, a voicecoil motor (VCM) actuator operating based on electromagnetic interactionbetween magnets and driving coils may be used to drive the optical lens.However, if misalignment occurs between the magnets and the drivingcoils or between the magnets and yokes, control performance of acorrection operation is decreased.

SUMMARY

The present invention provides a handshake correction apparatus capableof improving control performance of a correction operation by ensuringalignment between assembly parts including magnets and yokes.

According to an aspect of the present invention, there is provided ahandshake correction apparatus including a lens support plate thatsupports a correction lens and operates in a direction perpendicular toan optical axis; a base that supports the lens support plate to bemovable; and magnets and driving coils which are assembled on the lenssupport plate and the base to face each other, wherein the magnets aretight-fitted in assembly grooves of the lens support plate or the base,and wherein one or more protrusions that protrude from internal walls ofthe assembly grooves toward the magnets and elastically press themagnets are formed in the assembly grooves.

The internal walls of the assembly grooves, which face the one or moreprotrusions, may function as flat reference surfaces.

The one or more protrusions may be formed on the internal walls thatface the magnets in different directions.

The assembly grooves may have a rectangular shape defined by twohorizontal walls and two vertical walls, which are separately parallelto each other, the one or more protrusions may be formed on one of thehorizontal walls and one of the vertical walls, and the other one of thehorizontal walls and the other one of the vertical walls may function asflat reference surfaces.

The one or more protrusions may be formed on all of the internal wallsof the assembly grooves, which surround the magnets.

The one or more protrusions may include one or more first protrusionsthat are relatively easy to be elastically deformed; and one or moresecond protrusions that are relatively difficult to be elasticallydeformed. In this case, the one or more first protrusions may be formedto have a hollow shape.

The one or more protrusions may include one or more first protrusionsthat have a relatively small protruding thickness toward the magnets;and one or more second protrusions that have a relatively largeprotruding thickness toward the magnets.

The one or more protrusions may be integrally formed with the internalwalls of the assembly grooves. Alternatively, the one or moreprotrusions may include elastic members interposed between the magnetsand the internal walls of the assembly grooves.

According to another aspect of the present invention, there is provideda handshake correction apparatus including a lens support plate thatsupports a correction lens and operates in a direction perpendicular toan optical axis; a base that supports the lens support plate to bemovable; magnets and yokes which are assembled on the lens support plateand the base to face each other, and driving coils that are interposedbetween the magnets and the yokes, wherein the yokes are tight-fitted inassembly grooves of the lens support plate or the base, and wherein oneor more protrusions that protrude from internal walls of the assemblygrooves toward the yokes and elastically press the yokes are formed inthe assembly grooves.

The internal walls of the assembly grooves, which face the one or moreprotrusions, may function as flat reference surfaces. The one or moreprotrusions may be formed on the internal walls that face the yokes indifferent directions.

The assembly grooves may have a rectangular shape defined by twohorizontal walls and two vertical walls, which are separately parallelto each other, the one or more protrusions may be formed on one of thehorizontal walls and one of the vertical walls, and the other one of thehorizontal walls and the other one of the vertical walls may function asflat reference surfaces.

The one or more protrusions may be formed on all of the internal wallsof the assembly grooves, which surround the yokes.

The one or more protrusions may include one or more first protrusionsthat are relatively easy to be elastically deformed; and one or moresecond protrusions that are relatively difficult to be elasticallydeformed. In this case, the one or more first protrusions may be formedto have a hollow shape.

The one or more protrusions may include one or more first protrusionsthat have a relatively small protruding thickness toward the yokes; andone or more second protrusions that have a relatively large protrudingthickness toward the yokes.

The one or more protrusions may be integrally formed with the internalwalls of the assembly grooves. Alternatively, the one or moreprotrusions may include elastic members interposed between the yokes andthe internal walls of the assembly grooves.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other features and advantages of the present inventionwill become more apparent by describing in detail exemplary embodimentsthereof with reference to the attached drawings in which:

FIG. 1 is an exploded perspective view of a handshake correctionapparatus according to an embodiment of the present invention;

FIG. 2 is an assembled cross-sectional view of the handshake correctionapparatus illustrated in FIG. 1;

FIG. 3 is a plan view of a lens support plate illustrated in FIG. 1, towhich magnets illustrated in FIG. 1 are assembled;

FIG. 4 is a plan view of an assembly groove for a magnet, according toan embodiment of the present invention;

FIG. 5 is a plan view of an assembly groove for a magnet, according toanother embodiment of the present invention;

FIG. 6 is a plan view of an assembly groove for a magnet, according toanother embodiment of the present invention;

FIG. 7 is a plan view of an assembly groove for a magnet, according toanother embodiment of the present invention;

FIG. 8 is a plan view of an assembly groove for a magnet, according toanother embodiment of the present invention;

FIG. 9 is a plan view of an assembly groove for a yoke, according to anembodiment of the present invention;

FIG. 10 is a plan view of an assembly groove for a yoke, according toanother embodiment of the present invention;

FIG. 11 is a plan view of an assembly groove for a yoke, according toanother embodiment of the present invention;

FIG. 12 is a plan view of an assembly groove for a yoke, according toanother embodiment of the present invention; and

FIG. 13 is a plan view of an assembly groove for a yoke, according toanother embodiment of the present invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Hereinafter, the present invention will be described in detail byexplaining embodiments of the invention with reference to the attacheddrawings.

FIG. 1 is an exploded perspective view of a handshake correctionapparatus 100 according to an embodiment of the present invention. FIG.2 is an assembled cross-sectional view of the handshake correctionapparatus 100 illustrated in FIG. 1.

Referring to FIGS. 1 and 2, the handshake correction apparatus 100includes a correction lens 120, a lens support plate 130 on which thecorrection lens 120 is mounted, and a base 150 for supporting the lenssupport plate 130.

Magnets 135 are assembled at both sides (left/right sides) of the lenssupport plate 130, and driving coils 155 and yokes 160 are assembled ina vertical direction of the base 150 so as to face the magnets 135. Forexample, the driving coils 155 and the yokes 160 may be respectivelyassembled on upper and lower surfaces of the base 150 so as to face themagnets 135.

The magnets 135 and the driving coils 155 are located to face each otherand form, for example, a voice coil motor (VCM) actuator operating basedon electromagnetic interaction. Both ends of the driving coils 155 maybe connected to a circuit substrate (not shown) that applies acontrolled driving voltage. The lens support plate 130 is driven in anX-Y plane that is perpendicular to an optical axis (Z axis), based onthe electromagnetic interaction between the magnets 135 and the drivingcoils 155 and performs a correction operation.

In order to achieve stable control performance, the magnets 135 and thedriving coils 155 should be aligned so that their centers correspond toeach other. In this case, a horizontally symmetric driving force withrespect to center positions of the magnets 135, without being biasedtoward any side of the correction lens 120, is obtained, therebymaintaining a linear driving input/output correlation. For example, if amisalignment occurs between the magnets 135 and the driving coils 155,the driving force is horizontally biased toward one side of thecorrection lens 120, an undesirable rotation component is created inaddition to the driving force in X and Y axis directions, and left andright sides of the correction lens 120 have different correctionperformances. Such a defective correction operation causes image blur.The magnets 135 are assembled to be fitted in assembly grooves 130′formed in the lens support plate 130. As the magnets 135 aretight-fitted in the assembly grooves 130′ so as to maintain thealignment with the driving coils 155, an arbitrary dislocation may beprevented and the alignment may be maintained with high precision withinseveral micrometers, which will be described in detail later.

The magnets 135 and the yokes 160 are assembled to face each other andthus apply a magnetic attractive force to each other. The lens supportplate 130 closely approaches the base 150 due to the magnetic attractiveforce between the magnets 135 and the yokes 160, and returns to itsequilibrium position when the driving power is cut-off, by aligningcenters of the magnets 135 with the centers of the yokes 160.

The yokes 160 are required to maintain their positions with highprecision because an equilibrium position of the correction lens 120 isdetermined based on the positions of the yokes 160. The yokes 160 areassembled to be fitted in assembly grooves 150′ (see FIG. 2) formed inthe base 150. As the yokes 160 are tight-fitted in the assembly grooves150′, an arbitrary dislocation may be prevented and a position may bemaintained with high precision, which will be described in detail later.Meanwhile, the lens support plate 130 and the base 150 are disposed toface each other with ball bearings 140 (see FIG. 2) interposedtherebetween. The base 150 supports motion of the lens support plate 130on the X-Y plane through the ball bearings 140.

A cover 110 may be disposed on the correction lens 120. The cover 110 isassembled on the base 150 with the lens support plate 130 interposedtherebetween. A Hall sensor 115 for detecting the position of thecorrection lens 120 is assembled in the cover 110. The Hall sensor 115may detect displacement of the correction lens 120 that integrally moveswith the magnets 135, by sensing a change in a magnetic field of themagnets 135.

FIG. 3 is a plan view of the lens support plate 130 illustrated in FIG.1, to which the magnets 135 illustrated in FIG. 1 are assembled.

Referring to FIG. 3, assembly grooves 130′ into which the magnets 135are fitted are formed in the lens support plate 130, and one or moreprotrusions 131 that protrude toward the magnets 135 are formed in eachof the assembly grooves 130′. The magnets 135 are assembled into theassembly grooves 130′ by using a tight fit method, are elasticallypressed by the protrusions 131, and thus are firmly fixed in theassembly grooves 130′.

FIG. 4 is a plan view of an assembly groove 130′ for a magnet 135,according to an embodiment of the present invention.

Referring to FIG. 4, the assembly groove 130′ may be defined by fourinternal walls including two horizontal walls H and two vertical wallsV, which accommodate and fix the magnet 135, and the two horizontalwalls H and the two vertical walls V are separately parallel to eachother in a rectangular shape. As the magnet 135 is tight-fitted in theassembly groove 130′, a movement of the magnet 135 in the assemblygroove 130′ is suppressed and the position of the magnet 135, which isdetermined by the assembly groove 130′, is maintained.

The assembly groove 130′ includes protrusions 131 that protrude from theinternal walls toward the magnet 135 and elastically press the magnet135. As illustrated in FIG. 4, one of the horizontal walls H and one ofthe vertical walls V function as tight fit surfaces TFPs on which theprotrusions 131 are formed and the other one of the horizontal walls Hand the one of the vertical walls V function as flat reference assemblysurfaces SPs. The two reference assembly surfaces SPs stably support twoentire surfaces of the magnet 135 in the X and Y axis directions andthus the magnet 135 may be firmly fixed on a two-dimensional X-Y plane.The protrusions 131 formed on the tight fit surfaces TFPs face thereference assembly surfaces SPs and provide an elastic pressure to makethe magnet 135 closely contact the reference assembly surfaces SPs inthe X and Y axis directions.

The reference assembly surfaces SPs closely contact the two entiresurfaces of the magnet 135 and determine the position and orientation ofthe magnet 135. In more detail, the magnet 135 is pressed to closelycontact the reference assembly surfaces SPs and thus is fixed to theposition and orientation for contacting the reference assembly surfacesSPs.

One or more protrusions 131 that protrude toward the magnet 135 may beformed on each of the tight fit surfaces TFPs so as to press the magnet135 to closely contact the reference assembly surfaces SPs. When themagnet 135 is assembled, the protrusions 131 are compressed and press inan elastically biased state the magnet 135 to closely contact thereference assembly surfaces SPs. The protrusions 131 are formed of anelastic material capable of providing an appropriate elastic pressure.For example, the protrusions 131 may be formed of injection moldedplastic integrally with the lens support plate 130. For example, sincethe protrusions 131 provide a pressure corresponding to a compressionlevel and an elastic strength when the magnet 135 is assembled, aprotruding thickness t1 of and a material for forming the protrusions131 may be appropriately designed. If the elastic strength of theprotrusions 131 is excessive, the magnet 135 may not be easilyassembled. On the other hand, if the elastic strength of the protrusions131 is not sufficient, the magnet 135 may not be easily fixed.

The protrusions 131 are required to be elastically biased in acompression direction and to continuously provide a uniform elasticforce to the magnet 135, and thus may be formed of a material having ahigh fatigue resistance. Meanwhile, the protrusions 131 provided on thetight fit surfaces TFPs may be formed in an angular shape such as atriangular shape or a rectangular shape as well as a circular shape of ahemisphere.

FIG. 5 is a plan view of an assembly groove 230′ for a magnet 135,according to another embodiment of the present invention.

Referring to FIG. 5, the assembly groove 230′ is defined by two flatreference assembly surfaces SPs and two tight fit surfaces TFPs on whichprotrusions 231 are formed. As illustrated in FIG. 5, one of twohorizontal walls H and one of two vertical walls V function as tight fitsurfaces TFPs on which the protrusions 231 are formed and the other oneof the horizontal walls H and the one of the vertical walls V functionas the flat reference assembly surfaces SPs. In this case, one or moreprotrusions 231 may be formed on each of the tight fit surfaces TFPs andthe number of the protrusions 231 is not limited to as illustrated inFIG. 5.

FIG. 6 is a plan view of an assembly groove 330′ for a magnet 135,according to another embodiment of the present invention.

Referring to FIG. 6, the assembly groove 330′ is defined by one flatreference assembly surface SP and three tight fit surfaces TFPs on whichprotrusions 331 are formed. As illustrated in FIG. 6, one of twohorizontal walls H functions as the flat reference assembly surface SP,and the other one of the horizontal walls H and two vertical walls Vfunction as the tight fit surfaces TFPs on which the protrusions 331 areformed. In this case, one or more protrusions 231 may be formed on eachof the tight fit surfaces TFPs and the number of the protrusions 231 isnot limited to that illustrated in FIG. 5.

Since the reference assembly surface SP stably supports the entiresurface of the magnet 135 in the Y axis direction, the magnet 135 may befirmly fixed in the Y axis direction. The protrusions 331 formed on thetight fit surfaces TFPs provide an elastic pressure to make the magnet135 closely contact the reference assembly surface SP or provide anelastic pressure in the X axis direction to fix the magnet 135.

FIG. 7 is a plan view of an assembly groove 430′ for a magnet 135,according to another embodiment of the present invention.

Referring to FIG. 7, protrusions 431 are formed on all internal walls(two horizontal walls H and two vertical walls V) of the assembly groove430′, which surround the magnet 135. As the magnet 135 fitted in theassembly groove 430′ is elastically pressed from four directions, themagnet 135 is tightly fixed.

In this case, by differently designing the protrusions 431, some of theinternal walls may be designated as reference assembly surfaces SPs andthe others of the internal walls may be designated as tight fit surfacesTFPs. For example, the protrusions 431 may have different compressioncharacteristics by designing the protrusions 431 to have differentprotruding thicknesses t2 or by designing some of the protrusions 431 tohave a hollow shape. In this case, non-easily deformable protrusions 431may function as the reference assembly surfaces SPs and easilydeformable protrusions 431 may function as the tight fit surfaces TFPs.

FIG. 8 is a plan view of an assembly groove 530′ for a magnet 135,according to another embodiment of the present invention.

Referring to FIG. 8, additional elastic members 532 are interposedbetween the magnet 135 and internal walls of the assembly groove 530′.The elastic members 532 fix the magnet 135 by providing an elasticpressure to corresponding surfaces of the magnet 135. For example, theelastic members 532 may stably fix the magnet 135 in a two-dimensionalX-Y plane by pressing the magnet 135 in the X and Y axis directions. Forthis, concave grooves 530″ that match the elastic members 532 may beformed on horizontal and vertical walls H and V of the assembly groove530′ and the elastic members 532 may be disposed in the concave grooves530″. For example, the elastic members 532 may be formed in a rod shapehaving a circular cross-section. Meanwhile, protrusions 531 that may beintegrally formed with the internal walls of the assembly groove 530′may face the elastic members 532.

Structures of an assembly groove for a yoke will now be described withreference to FIGS. 9 through 13.

FIG. 9 is a plan view of an assembly groove 150′ for a yoke 160,according to an embodiment of the present invention.

Referring to FIG. 9, the assembly groove 150′ includes protrusions 151that protrude from internal walls (two horizontal walls H and twovertical walls V) toward the yoke 160 and elastically press the yoke160. As illustrated in FIG. 9, one of the horizontal walls H and one ofthe vertical walls V function as tight fit surfaces TFPs on which theprotrusions 151 are formed and the other one of the horizontal walls Hand the one of the vertical walls V function as flat reference assemblysurfaces SPs. The two reference assembly surfaces SPs stably support twoentire surfaces of the yoke 160 in the X and Y axis directions and thusthe yoke 160 may be firmly fixed in a two-dimensional X-Y plane. Theprotrusions 151 formed on the tight fit surfaces TFPs are disposed toface the reference assembly surfaces SPs and provide an elastic pressureto make the yoke 160 closely contact the reference assembly surfaces SPsin the X and Y axis directions. Meanwhile, technical features of theprotrusions 151 are substantially identical to the technical feathers ofthe protrusions 131 illustrated in FIG. 4 and thus a detaileddescription thereof will be omitted here.

FIG. 10 is a plan view of an assembly groove 250′ for a yoke 160,according to another embodiment of the present invention.

Referring to FIG. 10, the assembly groove 250′ is defined by two flatreference assembly surfaces SPs and two tight fit surfaces TFPs on whichprotrusions 251 are formed. As illustrated in FIG. 10, one or moreprotrusions 251 may be formed on each of the tight fit surfaces TFPs andthe number of the protrusions 251 is not limited to as illustrated inFIG. 10.

FIG. 11 is a plan view of an assembly groove 350′ for a yoke 160,according to another embodiment of the present invention.

Referring to FIG. 11, the assembly groove 350′ is defined by one flatreference assembly surface SP and three tight fit surfaces TFPs on whichprotrusions 351 are formed. As illustrated in FIG. 11, one of twohorizontal walls H functions as the flat reference assembly surface SP,and the other one of the horizontal walls H and two vertical walls Vfunction as the tight fit surfaces TFPs on which the protrusions 351 areformed. Since the reference assembly surface SP stably supports a wholesurface of the yoke 160 in the Y axis direction, the yoke 160 may befirmly fixed in the Y axis direction. The protrusions 351 formed on thetight fit surfaces TFPs provide an elastic pressure to make the yoke 160closely contact the reference assembly surface SP or provide an elasticpressure in the X axis direction to fix the yoke 160.

FIG. 12 is a plan view of an assembly groove 450′ for a yoke 160,according to another embodiment of the present invention.

Referring to FIG. 12, protrusions 451 are formed on all internal walls(two horizontal walls H and two vertical walls V) of the assembly groove450′, which surround the yoke 160. As the yoke 160 fitted in theassembly groove 450′ is elastically pressed from four directions, theyoke 160 is tightly fixed. In this case, some of the internal walls maybe designated as reference assembly surfaces SPs and the others of theinternal walls may be designated as tight fit surfaces TFPs, bydifferently designing the protrusions 451. For example, the protrusions451 may have different compression characteristics by designing theprotrusions 451 to have different protruding thicknesses t3 or bydesigning some of the protrusions 451 to have a hollow shape. In thiscase, non-easily deformable protrusions 451 may function as thereference assembly surfaces SPs and easily deformable protrusions 451may function as the tight fit surfaces TFPs.

FIG. 13 is a plan view of an assembly groove 550′ for a yoke 160,according to another embodiment of the present invention.

Referring to FIG. 13, additional elastic members 552 are interposedbetween the yoke 160 and internal walls of the assembly groove 550′. Theelastic members 552 fix the yoke 160 by providing an elastic pressure tocorresponding surfaces of the yoke 160. For example, the elastic members552 may stably fix the yoke 160 in a two-dimensional X-Y plane bypressing the yoke 160 in the X and Y axis directions. For this, concavegrooves 550″ that match the elastic members 552 may be formed onhorizontal and vertical walls H and V of the assembly groove 550′ andthe elastic members 552 may be disposed in the concave grooves 550″. Forexample, the elastic members 552 may be formed in a rod shape having acircular cross-section. Meanwhile, protrusions 551 that may beintegrally formed with the internal walls may face the elastic members552.

Meanwhile, the handshake correction apparatus 100 illustrated in FIG. 1may be disposed in a camera having a barrel structure. The barrelstructure may be a retractable barrel structure in which a barrelassembly is moved into/from the camera according to an on/off state ofthe camera, or a inner zoom barrel structure having an optical systemthat is vertically arranged based on an incident direction of lightreflected from a subject.

As described above, according to the present invention, assembly partsincluding magnets and yokes may be prevented from being arbitrarydislocated from their positions and may be fixed at their positions withhigh precision, by improving assembly structures of the assembly parts.As such, a non-linear characteristic between driving input and output,which is caused by misalignment, may be removed and a uniform correctionperformance may be ensured regardless of a driving direction, byensuring alignment between the magnets and the yokes, and between themagnets, the yokes, and driving coils for electromagnetic interaction.

For the purposes of promoting an understanding of the principles of theinvention, reference has been made to the preferred embodimentsillustrated in the drawings, and specific language has been used todescribe these embodiments. However, no limitation of the scope of theinvention is intended by this specific language, and the inventionshould be construed to encompass all embodiments that would normallyoccur to one of ordinary skill in the art.

The present invention may be described in terms of functional blockcomponents and various processing steps. Such functional blocks may berealized by any number of components configured to perform the specifiedfunctions.

The particular implementations shown and described herein areillustrative examples of the invention and are not intended to otherwiselimit the scope of the invention in any way. For the sake of brevity,conventional electronics, and other functional aspects of the systems(and components of the individual operating components of the systems)may not be described in detail. Furthermore, the connecting lines, orconnectors shown in the various figures presented are intended torepresent exemplary functional relationships and/or physical or logicalcouplings between the various elements. It should be noted that manyalternative or additional functional relationships, physical connectionsor logical connections may be present in a practical device. Moreover,no item or component is essential to the practice of the inventionunless the element is specifically described as “essential” or“critical”.

The use of the terms “a” and “an” and “the” and similar referents in thecontext of describing the invention (especially in the context of thefollowing claims) are to be construed to cover both the singular and theplural. Furthermore, recitation of ranges of values herein are merelyintended to serve as a shorthand method of referring individually toeach separate value falling within the range, unless otherwise indicatedherein, and each separate value is incorporated into the specificationas if it were individually recited herein. Finally, the steps of allmethods described herein can be performed in any suitable order unlessotherwise indicated herein or otherwise clearly contradicted by context.

Numerous modifications and adaptations will be readily apparent to thoseskilled in this art without departing from the spirit and scope of thepresent invention.

What is claimed is:
 1. A handshake correction apparatus comprising: alens support plate that supports a correction lens and operates in adirection perpendicular to an optical axis; a base that supportsmovement of the lens support plate; one or more magnets that aretight-fitted in assembly grooves of the base; one or more driving coils(yokes) that are assembled on the lens support plate to face the one ormore magnets; and one or more protrusions are formed in the assemblygrooves and protrude from internal walls of the assembly grooves towardthe magnets to elastically press the magnets.
 2. The apparatus of claim1, wherein the assembly grooves are surrounded in a plane by the base.3. The apparatus of claim 1, wherein the internal walls of the assemblygrooves, which face the one or more protrusions, serve as flat referencesurfaces.
 4. The apparatus of claim 1, wherein the one or moreprotrusions are formed on the internal walls that face the magnets indifferent directions.
 5. The apparatus of claim 1, wherein: the assemblygrooves have a rectangular shape defined by two horizontal walls and twovertical walls, which are separately parallel to each other; the one ormore protrusions are formed on one of the horizontal walls and one ofthe vertical walls; and the other one of the horizontal walls and theother one of the vertical walls serve as flat reference surfaces.
 6. Theapparatus of claim 1, wherein the one or more protrusions are formed onall of the internal walls of the assembly grooves, which surround themagnets.
 7. The apparatus of claim 1, wherein the one or moreprotrusions comprise: one or more first protrusions that are relativelyeasy to be elastically deformed; and one or more second protrusions thatare relatively difficult to be elastically deformed.
 8. The apparatus ofclaim 7, wherein the one or more first protrusions are formed to have ahollow shape.
 9. The apparatus of claim 1, wherein the one or moreprotrusions comprise: one or more first protrusions that have arelatively small protruding thickness toward the magnets; and one ormore second protrusions that have a relatively large protrudingthickness toward the magnets.
 10. The apparatus of claim 1, wherein theone or more protrusions are integrally formed with the internal walls ofthe assembly grooves.
 11. The apparatus of claim 1, wherein the one ormore protrusions comprise elastic members interposed between the magnetsand the internal walls of the assembly grooves.
 12. A handshakecorrection apparatus comprising: a lens support plate that supports acorrection lens and operates in a direction perpendicular to an opticalaxis; a base that supports movement of the lens support plate; one ormore driving coils (yokes) that are tight-fitted in assembly grooves ofthe base; one or more magnets that are assembled on the lens supportplate to face the one or more yokes; and one or more protrusions areformed in the assembly grooves and protrude from internal walls of theassembly grooves toward the yokes to elastically press the yokes. 13.The apparatus of claim 12, wherein the assembly grooves are surroundedin a plane by the base.
 14. The apparatus of claim 12, wherein theinternal walls of the assembly grooves, which face the one or moreprotrusions, serve as flat reference surfaces.
 15. The apparatus ofclaim 12, wherein the one or more protrusions are formed on the internalwalls that face the yokes in different directions.
 16. The apparatus ofclaim 12, wherein: the assembly grooves have a rectangular shape definedby two horizontal walls and two vertical walls, which are separatelyparallel to each other; the one or more protrusions are formed on one ofthe horizontal walls and one of the vertical walls; and the other one ofthe horizontal walls and the other one of the vertical walls serve asflat reference surfaces.
 17. The apparatus of claim 12, wherein the oneor more protrusions are formed on all of the internal walls of theassembly grooves, which surround the yokes.
 18. The apparatus of claim12, wherein the one or more protrusions comprise: one or more firstprotrusions that are relatively easy to be elastically deformed; and oneor more second protrusions that are relatively difficult to beelastically deformed.
 19. The apparatus of claim 18, wherein the one ormore first protrusions are formed to have a hollow shape.
 20. Theapparatus of claim 12, wherein the one or more protrusions comprise: oneor more first protrusions that have a relatively small protrudingthickness toward the yokes; and one or more second protrusions that havea relatively large protruding thickness toward the yokes.
 21. Theapparatus of claim 12, wherein the one or more protrusions areintegrally formed with the internal walls of the assembly grooves. 22.The apparatus of claim 12, wherein the one or more protrusions compriseelastic members interposed between the yokes and the internal walls ofthe assembly grooves.